# Constructing a Fluidyne Engine: Questions & Answers

• arehman1289
In summary, the dimensions of the tubes and the displacer are critical to engine performance, but there are mathematical equations governing the motion of the oscillating columns.

#### arehman1289

Can anyone help me in constructing a basic fluidyne engine to pump water. is the dimensioning of the tubes etc critical. any link/person can help me regarding this ??

Sure thing!

There is an excellent report prepared by Oak Ridge National Laboratory available which covers all the dynamics of using fluidyne engines to pump water for irrigation. Yes, the demensioning of the tubes is one of the main variables in determining engine performance, but happily, the dynamic continues to work across a broad range of possible values. So in other words, even if you just threw something together, it probably will work; but the equations involved scale well and are relatively easy to work with...

ORNLITM-10475 is the paper's official number. Let me see if I can find you a link.

And here it is: www.ornl.gov/~webworks/cppr/y2001/rpt/27113.pdf[/URL]

I think you'll find it's as complete a reference as you'll need to do all your calculations. If you have any trouble, ask about it and I'm sure we can hammer out the actual dimensions you'll want to use.

Hope it helps.

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very nice link mate. very informative. i hope u will help me if i have any problems while constructing it.
thank u

Certianly. I'm glad it fills the bill. Let me know if you want to discuss any particulars...

Incidentally, there's someone who's been posting YouTube videos of small example fluidynes running... It's a little odd, because while the engines are very nicely made, and the videos well-produced, he doesn't seem to be showing any actual use-- it's just the engine running. The reason I am bringing the video to your attention is that they give a very good impression of the frequency the engines oscillate at, and what that looks like.

All the best for your build effort!

yes i viewed some of those videos.
i plan to operate a pump using this engine but at the moment i am constructing a small prototype version. it is running but not that smoothly as expected.
i wanted to ask about the allowable variation in the diameter and lengths of the tubes used ??

hey there
can anyone give me research paper or tell me the mathematical equations that govern a fluidyne pump.
specifically if i want a required power output how to calculate
1) the heat input required
2) the dimensioning required of the displacer and tuning columns
3) predict the motion of the oscillating columns

## 1. What is a Fluidyne engine?

A Fluidyne engine is a type of heat engine that operates by converting the energy from heated air or steam into mechanical work. It uses a combination of air, water, and heat to create a cycle that produces rotational motion, similar to a steam engine.

## 2. How does a Fluidyne engine work?

A Fluidyne engine works by heating a fluid, such as air or water, in a closed system. The heated fluid expands, creating pressure and pushing against a piston. The piston then moves, converting the pressure into mechanical work. As the fluid cools, it contracts and the piston returns to its original position, creating a continuous cycle of motion.

## 3. What are the advantages of using a Fluidyne engine?

Fluidyne engines have several advantages, including their simplicity, low maintenance requirements, and ability to use a variety of heat sources. They can also be easily scaled up or down to fit different power needs, and their efficiency is not affected by changes in temperature or pressure.

## 4. What are some potential applications of Fluidyne engines?

Fluidyne engines can be used in a variety of applications, including power generation, water pumping, and propulsion systems. They can also be used in remote or off-grid locations, as they can run on a variety of heat sources, such as solar, biomass, or waste heat.

## 5. Are there any limitations to using a Fluidyne engine?

One limitation of Fluidyne engines is their lower power output compared to traditional heat engines, such as steam turbines. They also require a steady heat source to maintain their operation. Additionally, the design and construction of a Fluidyne engine may be more complex and require more specialized knowledge compared to other types of engines.